EVA
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EVA
ouis'd in their Paflage, and remark all the Changes that Save befallen them. And as thofe Alterations have fome- ti'mes been owing to Caprice, or Hazard, 'tis eafy- to take a mere Imagination, or Conje-aure, for a regular Analogy ; fo that 'tis nothing Grange the Public fhould be preju- diced againft a Science which feems to ftand on 10 pre- carious a Footing.
EVACUANTS, in Medicine, Remedies proper to expel, or carry off any ill, peccant, or redundant Humor in the animal Body ; by the proper Ways or Emuniiories. See Evacuation.
Of JBvacnauts, there are divers Kinds, diffinguifh'd ac- cording to their various Humours and Emunctories. See Humor and Emunctory.
Some, e. gr. carry off their Matters by Stool, call'd Purgatives, or Catharticks. See Purgatives, iSc. Others by Urine, call'd Diureticks. See Diureticks.
r"Vli^.-c l-m CDovFhir/ltim, rall'd c 7'li/ti>,
Others by Perforation, call'd 'Diaphorericks. See Dia- phoreticks. Others by Sweat, call'd Sudorieicks. Others by the Mouth, call'd Vomitories, or Emeticks. Others by the falival Glands, as SiAligogues : And othirs, laftly, by the Menfes, as Menagogues and Ari- stoloch icks.
EVA UATION, in Medicine, a Diminution of the animal Fluids, in Order to a Difcharge of fome morbid, or redundant Matters therein ; or, only, for the Sake of thinning, attenuating, and promoting the Motion and Cir- culation thereof. See Evacuants.
The Matter of a Difeafe, or what is prefcribed by Art to remove or eafe it, is Evacuated two Ways.
i°. By the natural Emunctories, or Out-lets of the Skin; the Noftrils, Mouth, Fauces, Oefophagus, Ventricle, Inteftines, Eladder, and Urethra.
And 2°. By artificial Outlets, made either in the Blood Veifcls ; as by Phlebotomy, Arteriotoray, Scarifications, and Leaches. See Phlebotomy and Scarification,^. Or, in the Lymphatic Vefl'els ; as by Causticks and Vesicatories. Or, laftly, in both, as by JJJ'ucs, Setons, Ulcers, Fiftula's, &c. See Issue, Seton, Fistula, i5c.
Hence, the firft Dittinction of Evacuants is derived from the different Emuntlories ; and the 2 d, from the Diversity of Matter evacuated thro' them.
Mod of the Chronical Difcafes, the Infirmities of old Age, and the fhort Periods of the Lives of Englishmen, Dr. Cheyne obferves, are owing to Repletion. This is evident from hence ; that Evacuation of one Kind or anoiher, is nine Parts in ten of their Remedy : For not only Cupping, Bleeding, Buffering, Iffucs, Purging, Vomit- ing and Sweating, are manifest Evacuations, or Drains, to draw out what has been fuperHuoufly taken down ; but even Abfiinence, Exercife, Alteratives, Cordials, Bitters, ^Sc. are but feveral Means to difpofe the grofs Flumours, River, <JC. to be more readily evacuated by infeniibie Perforation. EJfay on Health.
For the Periodical Evacuations of Women. See Menses.
For the Evacuations of Women after Delivery. See Lochia.
The Term is likewife ufed in the Art of War : To Evacuate a Place, is to make the Garrifon quit, or march cut of it, in order for another Power to take Pof- fefEon of it, or to make Room for another Garrifon.
EVANGELISTS, the infpired Authors of the Gofpels. See Gospel.
The Name Evangelifts was likewife given, in the antient Church, to fuch as preach'd the Gofpel here and there; without being attach'd to any particular Church. In which Senfe, ibme Interpreters think it is, that St. <Philip, who was one of the feven Deacons, is call'd the Evan- gclift, in 21 ft Chapter of the AHs of the Apoftles, Ver. 8. .Again, St. Paul writing to -Timothy, Ep. 2. C. IV. v. 5. bids^him do the Work of an Evangeiifl. The fame
Evanid are the fame with thofe othetwife call'd Fanta- flical, and Empbatical Colours : See Fantastical,. &e. EVANTES, in Antiquity, the Priefteffes of Bacchus 5 thus call'd, by Reafon, in celebrating the Orgia, they ran about, as if diflrafted, crying Evan, Evan, Qhe Evan I See Bacchantes.
EVAPORATION", in Philofophy, the Aft of exhaling the Humidity of a Body ; or of diflipating i t i n Fumes or Vapour. See Vapour.
Common Salt is form'd, by evaporating all the Humidity in the Salt- Water, or Brine; which Evaporation is either perform'd by the Heat of the Sun, as in the Salt-Works by the Sea Coaft, ($c. or by Means of Fire, as in the Salt Springs, (Sc. See Salt.
By the Obfervations of Monf. Sedileau it appears, that what is rais'd in Vapour, exceeds that which falls in Rain. See Rain.
Tho' the Evaporation of Liquids is generally look'd on as an Effect of the Heat, and the ' Motion of the Air ; yet Monf". Gauteron, in the Memoirs de V Academ- ies Scien. An. 1705. mews, that a quite oppofitc Caufe may have the fame Effect; and that Liquids lofe a deal more of their Parts in the feverefl Frof't, than when the Air is moderately warm. In the great Froft of the Year 1708, he found, that the greater the Cold, Hill the more confidcrable the Evaporation ; and that Ice it felf loft full as much as the warmer Liquors that did not freeze. See Frost.
Dr. Halley furniflies us with fome Experiments of the Quantity, or Mea r ure of the Evaporation of Water. — The Refult is contain'd in the following Articles :
1°. That Water faked to about the fame Degree as Salt Water, and expofed to a Heat equal to that of a Sum- mer's Day, did, from a circular Surface of about Eight Inches Diameter, Evaporate at the Rate of 6 Ounces in 24 Hours. Whence, by a Calculus, he finds, that the ThickneCs of the Pellicle, or Skin of Water Evaporated in two Hours, was the 53^ Part of an Inch: But, for a round Number, he fuppofes it only a do th Part ; and argues thence, that if Water as warm as the Air in Sam- mer, evaporates the Thicknefs of one 60th Part of an Inch in two Hours, from its whole Surface ; in twelve Hours it will exhale one tenth of an Inch. Which Quan- tity, he obferves, will be found abundantly fuffieicnr to furnilh all the Rains, Springs, Dews, S?c. Sec Spring, SSr. In Effect, on this Principle, every 10 Square Inches of the Surface of the Water, yields in Vapour, per diem, a Cubic Inch of Water; and each Squate Foot half a Wine Pint; every Space of 4 Foot Square, a Gallon; a Mile
Square, S914 Tons ; and a Square Degree, fuppofe of 69 Englifi Miles, will Evaporate 33 Millions of Tons. See ,iSc.
A Surface of Eight Square Inches, Evaporated, purely by the natural Warmth of the Water without either Wind or Sun, in the Courfc of a whole Tear, 16292 Grains of Water, or 64 Cubic Inches ; confequently, the Depth of Water thus Evaporated in one Year amounts to 8 Inches. But this being much too little to anfwer the Experiments of the French, who found, that it rain'd 1 9 Inches of Water in one Year at Paris ; or thofe of Mr. Tovinley, who found the Annual Quantity of Rain in Lancajhire, above 40 Inches : He concludes, that the Sun and Wind conlri- bute more to Evaporation, than any internal Heat, or Agitation pf die Water. See Rain.
3 . The Effect of the Wind is very confidcrable, on a double Account. For the fame Obfervations fhew a very odd Quality in the Vapqurs of Water, viz. that of adher- ing and hanging to the Surface that exhaled 'em, which they clothe, as it were, with a Fleece of vaporous Air ; which once inverting the Vapour, it thenceforwards rifes in much lefs Quantity. Whence, the Quantity of Water loll in 24 Hours, when the Air was very itill from Winds, .was very fmallj
1. proportion to what went away when there was a firong Apoftle, Eph. IV. 11. ranks the Evangelifts after the G J e £ f ^ ^^ ^ ^ ^ ^^ ^ ^
onH |Ji-rtnrlf>fc? .*^ /- 1 . -- ^ ~-»- L a i 1 - .li
Apoftlcs and Prophets.
Hence, Monf. Tillemont takes the Liberty to ufc the Word in the fame Senfe. ' Moft of thofe who then em-
- braced the Faith, being fill d with the Love of a holy
■ Philofophy, began to otiftribute their Goods to, the Poor, ' and after that went into divers Countries to do the Office ' of Evangelifts, to preach Chriil to fuch as had not yet ' heard of him, and to furnifb. them with the facred Wri-
- tings of the Gofpel.'
The Word is derived from the Greek, tvayfiHiw, form'd of iO, bene, well, and a>JlA©-, Angel, MejJ'enger.
Room for the EmifTion of Vapour: And this, even tho' the Experiment was made in a Place as clofe from the Wind as could be contrived.
Add, that this Fleece of Water hanging on the Surface of Waters in ftill Weather, is the Occafion of* very Grange Ap- pearances, by the Refraction of the Vapour's differing from, and exceeding that of common Air. Whence every Thing appears rais'd, as Houfes like Steeples, Ships as on Land above the Water, the Land rais'd, and as it were lifted from the Sea, iSc.
4°- The fame Experiments drew, that the Evaporations
O [naves Epijiclas tuas uno tempore mihi datas duas ! j n May, June, July, and Juguft, which arenearly equal, are quibus Evangelia quae reddam tiefcio ; deberi quidem about three Times as areat as thofe in the Months ot No-
jlane fateor. Cic. ad Attic.
EVANID. A Name fome Authors give to thofe Co- lours which are not of very long Duration ; as thofe in the Rain-bow, in Clouds before and after Sun- fet, £?c. See Colour, &c.
vember, ^December, January, and February.
Evaporation, in Pharmacy, an Operation by which the more anuecus and volatile Parts of Liquids are fpent, or drove awa'y in Steam ; *'o as to leave the remaining Part ftrongcr, or of a higher Confluence than before.
EvapO'
